Studies from the University of Arkansas, the University of Nevada and the University of Idaho have indicated that veterinary vaccine product efficacy is at risk due to improper handling and storage. Most animal vaccines require maintenance at refrigeration temperatures of 35-45 F. Yet these studies showed that anywhere from 25% to 76% of refrigerators used for vaccine storage in the livestock industry failed to maintain these temperatures.
In addition, other improper handling and storage procedures, including exposing vaccines to ultraviolet light from the sun or to temperature extremes and using improper injection techniques, can render vaccines less effective or even useless. Livestock do not gain immunity from vaccines that are damaged, destroyed or altered through improper handling and storage practices.
Two common types of vaccine are killed and modified live virus (MLV) vaccines. Killed vaccines are made by growing an organism that is inactivated or killed by utilizing chemicals or heat. MLV vaccines are made with a virus or bacterium that is attenuated, or weakened, so the organism will not cause disease in most healthy animals but will still stimulate immunity. Killed vaccines are considered safer but are typically not designed for long-term immunity.
MLV vaccines need to be reconstituted, as they are not stable in solution. Therefore, when mixing MLV vaccines, you should use the product within two hours and keep it cool—thus the need for a cooler and good management practices when storing syringe guns. The advantage of MLV products is they generally promote a longer active immune response.
Refrigeration temperature monitors can be a good investment. Monitor and record temperatures at least weekly. Consider the age of the appliance and the location (barn, porch or other storage areas) of the refrigerator. Refrigerator location can have a substantial impact on how efficiently the refrigerator operates. For example, a refrigerator kept in a noninsulated barn may be adversely affected by high and low ambient temperature extremes. These temperature extremes can damage products stored inside the refrigerator.
Some important tips to remember:
• Do not use vaccines that are or have been frozen.
• Never enter the vaccine bottle with a used needle.
• Practice good sanitation of equipment and the working environment.
• Triple rinse repeating syringes with boiling water, and don’t use a disinfectant, as this may inactivate vaccines following cleaning.
• Record product lot numbers, administration dates and withdrawal times.
• Read and follow label instructions.
• Maintain vaccination records for a minimum of three years. — Brian Freking, Oklahoma State University Extension Southeast District livestock specialist
